1. Field of the Invention
The invention relates to a water cooled air conditioner having a heat exchanger for an air conditioner refrigeration unit using water and air to cool the hot refrigerant in the condenser coils and a method for transferring heat from said condenser coils.
2. Description of the Related Art
In prior art air conditioners the condenser coils have been typically cooled in an air conditioner refrigeration system by pulling ambient air across the condenser coils with a fan inside the unit. The problem with these units is that they can be relatively inefficient in cooling the condenser coils, particularly as the ambient temperature rises. As the ambient temperature rises the efficiency rating goes down. When the ambient temperature is very hot, the efficiency rating of a high efficiency air conditioner may be no better than a standard air conditioner with an efficiency rating in the order of only 10.
Most air conditioning units for homes and small businesses are typically air cooled by blowing air over the condensing coils. For small commercial buildings, these units may be self contained units that include both the compressor, evaporator coils and condensing coils in the unit. These types of unit may be typically mounted on the roof of a building with the feed outlet of each unit connected to the feed ducting and a return air inlet connected to the return air ducting for a particular zone. Typically an air cooled condenser can lose 20% of its capacity as the outdoor temperature increases from 70° F. to 100° F. as compared to only about 4% for this invention.
It is known to improve the efficiency of the air conditioner units cooling of the condenser coils by running water over the coils instead of just air flow. After the water has run over the condenser coils and transferred heat from the coils to the water, it can be recirculated for continued cooling. After the water was cooled it was once again passed over the condenser coils. For very large air conditioning systems for large facilities it is common to use cooling towers with water recirculation to provide for removal of heat from the condensing unit to provide cooling.
U.S. Pat. No. 6,595,011 is a water cooled air conditioner. In this prior art, a water pump delivers water from the water tank through one or more water sprinklers into the inlet duct. A fan draws air into the inlet duct and through the air, which results in evaporation of the water and cooling of the air. The water of the water tank is maintained by a water valve and float. The compressor, the condenser coil and the accumulator are submerged in a body of water wherein the temperature of water is controlled by evaporative cooling.
U.S. Pat. No. 6,463,751 is an air conditioning unit that uses the condensate water to cool the condenser coil. Condensate from the evaporator is allowed to drip on the condenser coil itself, and this may be done by a trough at the top of the unit to direct the condensate. Also, U.S. Pat. No. 6,345,514 uses the condensate to cool the condenser. In this invention the condenser is on the outside of the compressor and there is a condensate distributor on top of the condenser to evenly distribute condensate over the condenser for cooling.
In another prior art invention, U.S. Pat. No. 6,338,256, special water cooling disk are installed in the center of a hollow heat exchange unit. The heat exchange unit formed by the refrigerant tubes and heat radiating fins that are installed upright in the unit. The one or more water cooling disk have water dripped on them and then the inertia of the rotation of the disk sprays the water onto the heat exchange unit and then the water runs down the unit.
It is known in the prior art to cool the water supplied to condenser coils in such systems adiabatically by circulating the water through an evaporative fill medium and then circulating the water in heat exchange relationship with the condenser coils. Ambient air is circulated through the evaporative fill medium while the water flows through the medium to thereby cool the water to a temperature approaching wet-bulb temperature before the water is supplied to the condenser coils. The water is then recirculated to the evaporative fill medium to effect cooling of the water in the manner just described. Because of evaporation, make-up water is automatically supplied to maintain an appropriate level of water in the system. Water heat exchangers are described, for example, in U.S. Pat. Nos. 4,182,131 and 4,603,559.
In the Bacchus U.S. Pat. No. 5,832,739 and Bacchus U.S. Pat. No. 5,992,171 the condenser coils are cooled by being covered with water in a channel on the bottom of the unit. The water was first cooled by a fan pulling air across the water as the water flowed down through an evaporative fill material, and when the water reached the end of the evaporative fill material it ran into one or more continuous serpentine channels, where the condenser coils were located